The present disclosure relates to a solid bowl screw centrifuge that includes a centrifuging chamber and a rotatable drum having a horizontal axis of rotation. The rotatable drum surrounds the centrifuging chamber. Also included is a rotatable screw arranged in the rotatable drum, at least one solids discharge, at least one liquid discharge duct and a peeling disk via which liquids are discharged through the liquid discharge duct. Further included is a blocking chamber connected to an output side of the peeling disk. The present disclosure further relates to a method for operation of the centrifuge.
A solid bowl screw centrifuge of the above-mentioned type is shown by German Patent Document DE 195 00 600 C1. German Patent Document DE 40 14 552 C1 shows a separator with a vertical axis of rotation having a peeling disk and a blocking disk between which a gas can be fed to prevent a degassing of solvents.
The solid bowl screw centrifuge disclosed in German Patent Document DE 43 20 265 A1 is equipped with a weir on the liquid outlet side, which weir has a passage. An orifice plate, which is stationary relative to the drum during its rotation, is assigned to the passage. By way of a threaded bush, this orifice plate is axially displaceable. By rotating the threaded bush, the distance between the weir and the orifice plate can be changed. The resulting change of the outflow cross-section causes a change of the liquid level in the centrifugal drum, so that a continuous adjustment of this liquid level can be achieved by displacing the orifice plate.
From German Patent Document DE 39 04 151 A1, a diaphragm plate situated on the screw is known. Nozzles on the outer circumference are used for minimizing the energy consumption. A processing of sensitive products with a gas-tight sealing-off with respect to the environment cannot be achieved by this construction.
From German Patent Document DE 198 30 653 C1 of the above-mentioned type, it is known to implement the liquid discharge of an open solid bowl screw centrifuge by of a peeling disk which is followed by a labyrinth seal, in order to return product droplets to the peeling disk. According to this construction, no sealing-off is required with respect to the exterior space. However, solid bowl screw centrifuges with peeling disks in which the product space is sealed off toward the outside are also in demand. The present disclosure addresses such a solid bowl screw centrifuge by simple constructive devices.